You could try

dnf history

which should give you more or less all package installing/removing/update actions you did via dnf. I don't really know how far this history gets back (in time).

Another place to get information about package modifications is to look into /var/log/yum.log. But the log is being rotated per default which will only give you a small time window to reconstruct the modifications.

man rpmgraph:

rpmgraph(8) - Linux man page
Name
rpmgraph - Display RPM Package Dependency Graph
Synopsis

rpmgraph PACKAGE_FILE ...
Description

rpmgraph uses PACKAGE_FILE arguments to generate a package dependency graph. Each
PACKAGE_FILE argument is read and added to an rpm transaction set. The elements 
of the transaction set

are partially ordered using a topological sort.

The partially ordered elements are then printed to standard output.


Nodes in the dependency graph are package names, and edges in the directed graph 
point to the parent of each node. The parent node is defined as the last 
predecessor of a package when partially ordered using the package dependencies as
a relation. That means that the parent of a given package is the package's last
prerequisite.

The output is in dot(1) directed graph format, and can be displayed or printed
using the dotty graph editor from the graphviz package. There are no rpmgraph
specific options, only common rpm options. See the rpmgraph usage message for    
what is currently implemented. 

  [1]: https://linux.die.net/man/8/rpmgraph

Installation:

rpm-devel fedora 19 has this package

Here is rpm-devel for fedora 30

Use your package manager:

dnf install rpm-devel

To install wget in CentOS, enter the following in a terminal window:

sudo yum install wget

To install wget in Fedora, enter the following:

sudo dnf install wget

Now, you can use the wget command to download the .rpm file you want. Enter the following:

wget http://some_website/sample_file.rpm

The system should reach out to the website and download the file to your current working directory.

Install RPM File Using RPM Command

To install a .rpm package in Fedora or CentOS Linux, enter the following:

sudo rpm –i sample_file.rpm

The –i switch tells the package manager you want to install the file.

More information on the RPM installer can be found in the RPM documentation.

Install RPM File With Yum

Alternately, you can use the yum package manager to install .rpm files.

Enter the following:

sudo yum localinstall sample_file.rpm

The localinstall option instructions yum to look at your current working directory for the installation file.

https://superuser.com/questions/483307/how-do-i-know-dependent-rpms-of-a-a-package

https://phoenixnap.com/kb/how-to-install-rpm-file-centos-linux

https://linux.die.net/man/8/rpm

EDIT:

I can't get rpmgraph to work, I've tried three different versions of PACKAGE_FILE syntax of package list, but it just gives errors, If you know how to use this program, please provide an answer or edit mine. Tested on Fedora 28.How to list all installed packages with the .rpm extension. Fedora, Centos, RedHat

# rpmgraph INSTALLED_PACKAGES 
(null): read manifest failed: